Generally, a motor vehicle, such as a motorcycle, a car, a boat, a personal water craft, etc., that is not in use and parked or placed outdoors is normally covered with a protective cover having a configuration matching with that of the vehicle, so that the vehicle is protected against dust, rainwater, snow, moisture, etc.
It is possible some parts of a vehicle, particularly an engine thereof, would have a residual heat once after the vehicle engine has been operated for a period of time. The protective cover covering the vehicle would also trap such residual heat and moisture in the air. It is necessary to remove the residual heat and moisture from inside of the protective cover to avoid adverse influences of such trapped residual heat and moisture on the vehicle. Therefore, the protective cover for motor vehicles must be made of a material that is not only waterproof but also air-permeable, and preferably provided at positions corresponding to, for example, the engine and other heat-producing parts of the vehicle with vents to timely dissipate the residual heat and moisture trapped in the protective cover.
FIG. 1 schematically shows a car (1) is covered with a protective cover (A) having a configuration corresponding to that of the car (1). It is shown that the protective cover (A) is provided at a suitable position with a venting structure (2) for heat and moisture trapped in the protective cover (A) to escape therefrom.
FIG. 2 is a fragmentary, enlarged perspective view of the protective cover (A) of FIG. 1 showing the conventional venting structure (2), and FIG. 3 is a sectioned side view of FIG. 2. As shown, the conventional venting structure (2) includes a vent (21) provided on the protective cover (A) at a desired position, such as an area corresponding to an engine (not shown) of the car vehicle (1), and a hood (22) sewed into the protective cover (A) to close three sides of the vent (21) with an opening (221) left as one side of the vent (21). That is, the hood (22) loosely covers the vent (21) to avoid the vent (21) from directly exposing to an external environment. The hood (22) is generally made of a rigid or a semi-rigid plastic material to have an arch configuration, so that a clear airflow passage (222) is formed and always maintained between the hood (22) and the vent (21). Any residual heat generated by the motor vehicle (1) and any moisture trapped in the protective cover (A) may escape from the protective cover (A) via the vent (21), the airflow passage (222), and the opening (221) of the hood (22), as indicated by the arrow “a”.
In FIG. 3, the wide opening (221) and the clear airflow passage (222) allow the residual heat and the moisture to escape from the protective cover (A). Rainwater is also admitted into the protective cover (A) via the vent (21), as indicated by the arrow “b”, when the protective cover (A) is subject to, for example, a rainstorm. That is, the existence of the vent (21) and the hood (22) prevents the protective cover (A) from being perfectly watertight in the rainstorm.
For the protective cover (A) to effectively protect the vehicle against rainwater, snow, etc., it is necessary to provide means for firmly tying the protective cover (A) to the vehicle being protected. In lacking of proper fastening or tying means, the protective cover (A) might very possibly become separated from the vehicle under strong wind and heavy rain and completely loses its intended function. Generally, the protective cover (A) for motor vehicles has three types of fastening structures. A first type of fastening structure for the protective cover (A) is shown in FIG. 4 and includes an elastic band (31) sewed to a lower edge of the whole protective cover (A). This type of fastening structure is workable under normal weather condition but not under strong wind and heavy rain. That is, the protective cover (A) with the elastic band (31) provided along the lower edge thereof would still be blown away or lifted by the strong wind. FIG. 5 shows the second type of fastening structure for the protective cover (A). Two grommets (32) are provided at two opposite sides of the protective cover (A) near two middle points thereof, so that a rope (not shown) may be extended through the grommets (32) to tie the protective cover (A) to the vehicle. Again, the provision of the grommets (32) does not effectively prevent the protective cover (A) from being blown off or lifted by strong wind. FIG. 6 shows the third type of fastening structure that is frequently found in the protective cover (A) for boats, and includes a plurality of tie-down loops (33) sewed to the lower edge of the protective cover (A). Ropes (34) are separately extended through the tie-down loops (33) for tying the cover (A) to the vehicle (1). However, it is very inconvenient and time-consuming to extend the ropes (34) through the tie-down loops (33) one by one. Therefore, it is desirable to develop an easily operable fastening structure for the vehicle protective cover, so that the latter could be well tightened on the vehicle being protected.